includes/SearchMySQL.php

   1 <?php
   2 # Copyright (C) 2004 Brion Vibber <brion@pobox.com>
   3 # http://www.mediawiki.org/
   4 #
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 2 of the License, or
   8 # (at your option) any later version.
   9 #
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13 # GNU General Public License for more details.
  14 #
  15 # You should have received a copy of the GNU General Public License along
  16 # with this program; if not, write to the Free Software Foundation, Inc.,
  17 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18 # http://www.gnu.org/copyleft/gpl.html
  19
  20 /**
  21  * Search engine hook base class for MySQL.
  22  * Specific bits for MySQL 3 and 4 variants are in child classes.
  23  * @addtogroup Search
  24  */
  25 class SearchMySQL extends SearchEngine {
  26         /**
  27          * Perform a full text search query and return a result set.
  28          *
  29          * @param string $term - Raw search term
  30          * @return MySQLSearchResultSet
  31          * @access public
  32          */
  33         function searchText( $term ) {
  34                 $resultSet = $this->db->resultObject( $this->db->query( $this->getQuery( $this->filter( $term ), true ) ) );
  35                 return new MySQLSearchResultSet( $resultSet, $this->searchTerms );
  36         }
  37
  38         /**
  39          * Perform a title-only search query and return a result set.
  40          *
  41          * @param string $term - Raw search term
  42          * @return MySQLSearchResultSet
  43          * @access public
  44          */
  45         function searchTitle( $term ) {
  46                 $resultSet = $this->db->resultObject( $this->db->query( $this->getQuery( $this->filter( $term ), false ) ) );
  47                 return new MySQLSearchResultSet( $resultSet, $this->searchTerms );
  48         }
  49
  50
  51         /**
  52          * Return a partial WHERE clause to exclude redirects, if so set
  53          * @return string
  54          * @private
  55          */
  56         function queryRedirect() {
  57                 if( $this->showRedirects ) {
  58                         return '';
  59                 } else {
  60                         return 'AND page_is_redirect=0';
  61                 }
  62         }
  63
  64         /**
  65          * Return a partial WHERE clause to limit the search to the given namespaces
  66          * @return string
  67          * @private
  68          */
  69         function queryNamespaces() {
  70                 $namespaces = implode( ',', $this->namespaces );
  71                 if ($namespaces == '') {
  72                         $namespaces = '0';
  73                 }
  74                 return 'AND page_namespace IN (' . $namespaces . ')';
  75         }
  76
  77         /**
  78          * Return a LIMIT clause to limit results on the query.
  79          * @return string
  80          * @private
  81          */
  82         function queryLimit() {
  83                 return $this->db->limitResult( '', $this->limit, $this->offset );
  84         }
  85
  86         /**
  87          * Does not do anything for generic search engine
  88          * subclasses may define this though
  89          * @return string
  90          * @private
  91          */
  92         function queryRanking( $filteredTerm, $fulltext ) {
  93                 return '';
  94         }
  95
  96         /**
  97          * Construct the full SQL query to do the search.
  98          * The guts shoulds be constructed in queryMain()
  99          * @param string $filteredTerm
 100          * @param bool $fulltext
 101          * @private
 102          */
 103         function getQuery( $filteredTerm, $fulltext ) {
 104                 return $this->queryMain( $filteredTerm, $fulltext ) . ' ' .
 105                         $this->queryRedirect() . ' ' .
 106                         $this->queryNamespaces() . ' ' .
 107                         $this->queryRanking( $filteredTerm, $fulltext ) . ' ' .
 108                         $this->queryLimit();
 109         }
 110
 111
 112         /**
 113          * Picks which field to index on, depending on what type of query.
 114          * @param bool $fulltext
 115          * @return string
 116          */
 117         function getIndexField( $fulltext ) {
 118                 return $fulltext ? 'si_text' : 'si_title';
 119         }
 120
 121         /**
 122          * Get the base part of the search query.
 123          * The actual match syntax will depend on the server
 124          * version; MySQL 3 and MySQL 4 have different capabilities
 125          * in their fulltext search indexes.
 126          *
 127          * @param string $filteredTerm
 128          * @param bool $fulltext
 129          * @return string
 130          * @private
 131          */
 132         function queryMain( $filteredTerm, $fulltext ) {
 133                 $match = $this->parseQuery( $filteredTerm, $fulltext );
 134                 $page        = $this->db->tableName( 'page' );
 135                 $searchindex = $this->db->tableName( 'searchindex' );
 136                 return 'SELECT page_id, page_namespace, page_title ' .
 137                         "FROM $page,$searchindex " .
 138                         'WHERE page_id=si_page AND ' . $match;
 139         }
 140
 141         /**
 142          * Create or update the search index record for the given page.
 143          * Title and text should be pre-processed.
 144          *
 145          * @param int $id
 146          * @param string $title
 147          * @param string $text
 148          */
 149         function update( $id, $title, $text ) {
 150                 $dbw = wfGetDB( DB_MASTER );
 151                 $dbw->replace( 'searchindex',
 152                         array( 'si_page' ),
 153                         array(
 154                                 'si_page' => $id,
 155                                 'si_title' => $title,
 156                                 'si_text' => $text
 157                         ), 'SearchMySQL4::update' );
 158         }
 159
 160         /**
 161          * Update a search index record's title only.
 162          * Title should be pre-processed.
 163          *
 164          * @param int $id
 165          * @param string $title
 166          */
 167     function updateTitle( $id, $title ) {
 168                 $dbw = wfGetDB( DB_MASTER );
 169
 170                 $dbw->update( 'searchindex',
 171                         array( 'si_title' => $title ),
 172                         array( 'si_page'  => $id ),
 173                         'SearchMySQL4::updateTitle',
 174                         array( $dbw->lowPriorityOption() ) );
 175         }
 176 }
 177
 178 /**
 179  * @addtogroup Search
 180  */
 181 class MySQLSearchResultSet extends SearchResultSet {
 182         function MySQLSearchResultSet( $resultSet, $terms ) {
 183                 $this->mResultSet = $resultSet;
 184                 $this->mTerms = $terms;
 185         }
 186
 187         function termMatches() {
 188                 return $this->mTerms;
 189         }
 190
 191         function numRows() {
 192                 return $this->mResultSet->numRows();
 193         }
 194
 195         function next() {
 196                 $row = $this->mResultSet->fetchObject();
 197                 if( $row === false ) {
 198                         return false;
 199                 } else {
 200                         return new SearchResult( $row );
 201                 }
 202         }
 203 }
 204
 205 ?>